The present invention relates to a compensated deflection yoke for cathode-ray tubes.
It is known that in the field of television sets and monitors in general the necessity arises to reduce the electromagnetic radiation produced by the horizontal windings of the deflection yokes. In order to reduce said radiation, coils, named bucking coils, are suitably arranged to the sides of the yoke body located at the rear end of the cathode-ray tube.
A great difficulty is encountered on mounting said coils, as they must be fixedly secured to the yoke body, in a suitable manner with respect to the electromagnetic field on which it is wished to operate and must be properly clamped.
At the present state of the art some monitor manufacturers have studied a compensating system provided with a bucking coil consisting of some turns of copper wire wound in the air, held together by some turns of insulating tape and fastened to the yoke partly by welding the terminals thereof to the yoke contacts and partly by means of silicone cements.
However this structure is rather precarious and not at all reliable as regards lifetime and efficiency.
Likewise there are some embodiments of handicraft type which generally exhibit the same structure as the one described above.
From the foregoing it appears that compensation cannot be a fine one and that the structure reliability of the coil is limited because said coil is not integrally fastened to the yoke body to which it belongs, but it is only secured through the terminals thereof, Finally, when fastening is carried out by means of cements it is not very reliable because the coil can be easily removed from its seat, which is already precarious by itself, when the monitor is subjected to sudden and strong shakes.
It is also to be pointed out that in such a precarious embodiment the calculus of compensation relating to the number of turns in bucking coils surely cannot be of high quality.
It is therefore an object of the present invention to find a solution which is capable of associating a reliability in use with a quick installation and high quality of yield.